Answer:
1, 2, 3
Step-by-step explanation:
X <= 20 means that x has to be less than OR equal to 20.
The first option is -100. That's less than 20, so this statement is true.
The second option is 10. That's also less than 20, so this statement is also true.
The third option is 20. This is equal to 20, so this is also true.
The fourth option is 21, which is greater than 20, so it's not true.
The fifth option is 45, which is greater than 20, so it's not true.
Sorry I answered so late, hope this helps even though you probably don't need it anymore.
Answer:
B: 0.8
Step-by-step explanation:
Just multiply then divide
The total R value is computed from the R-values of the components in the stack as ...
(inches of wood)*(R-value of wood) +(inches of fiberglass)*(R-value of fiberglass) +(inches of foam)*(R-value of foam)
= (4 in)(2 /in) +(2 in)(4 /in) +(3 in)(5 /in)
= 8 +8 +15
= 31
The total R-value of the wall is 31.